MicrobeHunter.com Microscopy Forum

Has anybody ever tried to add a reticle, such as a crosshatch, to a phase centering telescope?

Carl

Not exactly a reticle but I have a bent sewing pin inside mine to act like a pointer. The eyepiece (which screws out as a unit) appears to be Ramsden with something like 10 mm focal length and field number around 5 mm. The threads between the eyepiece and inner tube are fairly precise and can be left loose giving +/-1 mm range to focus the pointer.

Elaborating on Hans's post, assuming you have a phase telescope that is of Keplarian make, there is a virtual image of the objective back focal plane (BFP) to be observed just below the eyepiece. So if you can add a reticle at that plane, that will enable you to superimpose it on the BFP image. Just curious, but why do you want a reticle on one?

Cheers,
John

Thanks for the replies. For those curious, Olympus used a similar device to look into the light inlet port of the BHS scope, to collimate the substage lighting and field diaphragm.

Carl